Our goal is to create a more cost-efficient design for the economizer component of an HVAC device, under the sponsorship of MicroMetl Corporation. Economizers utilize a system of dampers designed to separate streams of frigid and hot air. When an HVAC unit detects that the outside air is sufficiently cool and dry, it will trigger the economizer to allow the intake of this ambient air into the building in question, which allows for a fresher quality of air than cooling down the re-circulated air. Economizers are prone to air leakage, wherein there is an intermingling of these two air streams. Our primary goal is to develop an economizer design that has a lower rate of air leakage than current designs, and ideally is cheaper to manufacture. Additionally, the very large number of units manufactured and sold signifies that any reduction in cost or improvement in efficiency would result in considerable saving for the company. This in combination with the easy scalability of the device has provided us significant creative freedom to accomplish our goals.
As a team we continue to make great effort in understanding the fundamentals and mechanics of the economizer system. We have researched different patents and scientific articles for help before entering the industry. Our project is related to the US economizer market within the HVAC industry. The US economizer market was valued at $7.7 billion in 2016 and is projected to reach $11.54 billion by 2022. New market trends within this market are focused on reducing operational/energy costs, using renewable energy, and improving building automation. The main objective for our team is to create an economizer damping unit that can reduce operation costs by either minimizing leakage or reducing the manufacturing costs per unit.
Being within the economizer market gives the team numerous competitors nationally. Some of the key players in the national/global market are Honeywell International Inc, Cain Industries, Johnson Controls International plc, and STULZ Air Technology Systems, Inc. After indicating our main competitors we researched the market trends and patterns within the industry. We found that the industrial segment is estimated to account for the largest share of the economizer market in 2017. Although residential segments have been rising due to the increase of construction and housing developments. Our team is working closely alongside MicroMetl to ensure optimal integration of our product into the existing infrastructure.
Proof of Concept
NV Heat Solutions is attempting to prove that our novel design exhibits a reduction in the air leakage rate when compared to current industry standard economizers while also operating more cost efficiently. We have access to equations that help determine the air leakage along gaps on the sides. These equations provide a standard that can be tested and calculated. The dampers in our design are made out of aluminum which has proven to be durable and cost effective. The use of aluminum is almost always used in commercial applications in HVAC components. The rubber application for providing a proper seal is well placed. The resilience and low cost of rubber help satisfy our project requirement specifications. The designs of the dampers allow for scalability. The symmetry and simplicity of the dampers allow for flexible dimensions that can adapt to different economizer designs and varieties. Actuators and motors will provide torque to the damper in order to turn in a proper manner. A combination of analysis and discussions with MicroMetl Corp. indicate the potential of our redesign moving forward in the course of our project.
NV Heat Solutions made a new and innovative design that is not only made to decrease air leakage rates but also decrease manufacturing cost. We completed this by making a novel design. Instead of using a normal rectangular blade we used hollow cylindrical tubes made of galvanized steel with offsetting blades on each side of the tube. The offset allows a tighter seal when closed reducing leakage while still maintaining air flow when open. We combined this with a rack and pinion system which will be linked to an actuator that drives the gears attached to the blades. This actuator will be controlling the gearing system and applying the forces needed to hold the damper blades in position. This damper design will not only decrease the air leakage of any current economizer system, but will also cost less than competitors due to our low manufacturing cost.
In terms of fabrication, the bushings and damper blades were made by additive manufacturing by 3-D printing. They are currently made out of ASA and TPU. TPU is called for the bushings due to its strength and flexible properties. ASA is used for the damper blades for its durability and strength. Since this prototype is a one-of, the bushings and damper blades would ideally be made out of hard plastic and sheet metal instead of weaker 3-D printing material. We have worked closely with MicroMetl for fabricating the frame and linkage system of our design, and fortunately we are able to use their facilities and machines for the build. The linkage system and frame will be made out of 18 gauge galvanized steel for it is the cheapest and most accessible option. The machines in operation for the fabrication are shears, brakes, and turrets. The shears perform the general cutting of the sheet metal. Brakes cause the bending of the sheet metal for the correct form. Finally, turrets provide the precise cuts and holes on the material.
The assembly for the prototype will include four damper blades; one damper blade will have a longer hexagonal shaft to which the actuator will be able grab and provide torque. The actuator is held by a smaller flange that allows for clearance. There will be a total of eight bushings that have square holes and one hexagonal hole that allow for rotation within the sides of the frame. The frame is put together with two sides, a top mount, and bottom mount. The linkage system will be placed on one side of the frame and be oriented as shown in figure 1. The linkages are held together by nuts and bolts that allow for smooth rotation. The frame will be bolted together which is similar to MicroMetl’s current line of economizers and to our proof of concept. Furthermore, the frames will be assembled with low leak angles at the top and bottom which will provide a reduced air leakage. Side seals which sit between the shafts and holes of the frame will also provide reduced air leakage. Assembly of the prototype is all done by hand and the use of power tools.
Testing and Results
The initial testing for our product consisted of fluid analysis using SolidWorks software. The team used the 3D model to measure how the airflow would react with our damper system once it was open or closed. The fluid analysis showed promise as we didn’t see too much leakage when the blades are open. While having good flow when the blades are open. This analysis showed a little problem however, as our blades had some collision issues while opening. Once the prototype was completed and checked through capstone the assembly will be shipped to Indiana in order to perform a more concise and accurate analysis on the leakage rate produced by the blades.
We performed our SolidWorks analysis once which yielded successful obstruction of air flow when closed. The pressure difference measured was 0.45 which shows promise and has a good rate. The only failure seen was within the gaps in the side seals and between blades which caused a little leakage through the airflow. These issues can be fixed with developing new side seals and adding flap seals on the edge of the blades to secure a better contact point and seal.
This project solves the problem of air leakage and cost inefficiency within some economizers. This is solved by saving energy and manufacturing costs with the simple design of single blades. The manufacturing process is cut down with less pieces to be put together this saving time and overhead costs. These results have created excitement within the company as the design has turned out to be promising and a cheaper alternative to their current blades. Although consumers are not aware of technology within dampers and economizers, companies like MicroMetl will be excited to save money and implement new designs.
|20% Edrylle Crowe|
|20% Etzal Corona|
|20% Keylan Rollins|
|20% Mateusz Podzorski|
|20% Tyler Koepf|
Meet the Team
Mateusz Podzorski is a native of Las Vegas, Nevada, who is currently enrolled in his senior year of study at the University of Nevada, Reno. He is pursuing a Bachelor of Science in Mechanical engineering, alongside a minor in Materials Science and Engineering. Mateusz is a national merit scholar, an honors student, and has studied abroad at Chonnam National University in Gwangju, Korea. In his time at UNR, Mateusz has worked in undergraduate research labs in both Chemical Engineering and Computer Science. After graduating in the Spring, Mateusz plans to continue pursuing higher education in a graduate program, where he will earn his doctorate in Mechanical Engineering.
Edrylle Crowe grew up in Sacramento, California and came to the University of Nevada, Reno in during the fall semester of 2013. Along with pursuing a Bachelor of Science in Mechanical Engineering, he is seeking to complete a minor in Renewable energy. During his time at the university, he has worked with a team that provided a lesson plan in the fundamentals of engineering and physics for a sophomore high school level class. Ed has previously worked in the composite manufacturing industry where he gained machine shop experience. A design solution that stood out for him was working with another colleague in implementing a streamlined assembly process of F-15 gun covers. The improvements saved time and made for more efficient and easier labor. After graduation in the spring, Ed is seeking to be involved in the manufacturing industry after graduation. He aims to finish his time at the university on a high note.
Keylan Rollins is from Las Vegas, Nevada and in his final year of his bachelor’s degree of Mechanical Engineering with a minor in Math/Statistics. He plans to further his education by pursuing a Masters in Business Administration at his current university, the University of Nevada Reno. Keylan is involved in many extracurricular activities such as the Boy Scouts of America, intramural sports, and volunteering. One of Keylan’s major goals is to someday own a respected engineering or construction firm that will work on a variety of projects.
Etzal Corona is a first generation college student born in Guadalajara, Mexico. Etzal is currently a senior at the University of Nevada, Reno pursuing a Bachelor’s of Science in Mechanical Engineering as well as a minor in Unmanned Autonomous Systems. Etzal’s interests include robotics, drones, control systems, and material. His goals are to utilize the skills developed at the University to work on sports equipment/technology, the automotive industry, or with robotics such as drones and animatronics. In order to further his knowledge of mechanical systems, Etzal plans on attending graduate school while looking to emphasize in robotics or materials. Etzal has developed technical skills within problem solving while becoming proficient in SolidWorks, MatLab, LabView, Excel, and some experience with C++ programing. During his undergraduate career, Etzal has applied his knowledge on various projects ranging from a hovercraft, evolutionary algorithms, constructing a multimeter, material design project, and an HVAC economizer for his senior capstone project.
Tyler Koepf is from San Francisco, California and is currently a senior at the University of Nevada, Reno. After graduation, Tyler plans to enter straight into the workforce. Tyler’s academic accomplishments include being in the top ten of his graduating class in high school and completing classes in advanced mathematics and physics during his time in college. During his time at UNR, Tyler has developed skills in problem solving, SolidWorks, Matlab, and Excel. During his sophomore year of college, Tyler build a bridge out of balsa wood which held a load of 352 pounds while only weighing 1.2 lbs.